Nilsson Martin, Kalckert Andreas
Department of Cognitive Neuroscience and Philosophy, Institute of Bioscience, University of Skövde, Skövde, Sweden.
Eur J Neurosci. 2021 Dec;54(11):7974-7988. doi: 10.1111/ejn.15534. Epub 2021 Nov 25.
How do we feel that we own our body? By manipulating the integration of multisensory signals and creating the illusory experience of owning external body parts and entire bodies, researchers have investigated the neurofunctional correlates of body ownership. Recent attempts to synthesize the neuroimaging literature of body ownership through meta-analysis have shown partly inconsistent results. A large proportion of functional magnetic resonance imaging (fMRI) findings on body ownership include analyses based on regions of interest (ROIs). This approach can produce inflated findings when results are synthesized in meta-analyses. We conducted a systematic search of the fMRI literature of ownership of body parts and entire bodies. Three activation likelihood estimation (ALE) meta-analyses were conducted, testing the impact of including ROI-based findings. When both whole-brain and ROI-based results were included, frontal and posterior parietal multisensory areas were associated with body ownership. When only ROI-based results were included, larger areas of the frontal and posterior parietal cortices and the middle occipital gyrus were associated with body ownership. A whole-brain meta-analysis, excluding ROI-based results, found no significant convergence of activation across the brain. These findings highlight the difficulty of quantitatively synthesizing a neuroimaging field where a large part of the literature is based on findings from ROI-based analyses. We discuss these findings in the light of current practices within this field of research and highlight current problems of meta-analytic approaches of body ownership. We recommend the sharing of unthresholded data as a means to facilitate future meta-analyses of the neuroimaging literature of body ownership.
我们如何感觉自己拥有自己的身体?通过操纵多感官信号的整合并创造拥有外部身体部位和整个身体的错觉体验,研究人员已经研究了身体所有权的神经功能相关性。最近通过荟萃分析来综合身体所有权神经影像学文献的尝试显示出部分不一致的结果。大量关于身体所有权的功能磁共振成像(fMRI)研究结果包括基于感兴趣区域(ROI)的分析。当在荟萃分析中综合结果时,这种方法可能会产生夸大的结果。我们对关于身体部位和整个身体所有权的fMRI文献进行了系统检索。进行了三项激活可能性估计(ALE)荟萃分析,测试纳入基于ROI的研究结果的影响。当同时纳入全脑和基于ROI的结果时,额叶和顶叶后部的多感官区域与身体所有权相关。当仅纳入基于ROI的结果时,额叶和顶叶后部皮质以及枕中回的更大区域与身体所有权相关。一项排除基于ROI结果的全脑荟萃分析发现,全脑激活没有显著的汇聚。这些发现凸显了定量综合一个神经影像学领域的困难,该领域的大部分文献基于基于ROI分析的结果。我们根据该研究领域内的当前做法讨论这些发现,并强调身体所有权荟萃分析方法当前存在的问题。我们建议分享未阈值化的数据,作为促进未来身体所有权神经影像学文献荟萃分析的一种手段。